More dense than Love~ (Kurasuma x Korosensei)

Chapter 10: Just sex

-I apologize in advance for my inexperience in writing gay smut-

Karasuma moaned sharply as the small tentacle slid into him. Karasuma huffs, pumping Korosensei's length slowly. Korosensei's suddenly leaned back, and pulled his knees back. Karasuma blushed like mad.
"W-Wait you want me to... Are you sure?" He asks, looking down at his own length nervously, then at Korosensei's tight ass. Korosensei blushes heavily, turning pink.
         "I'm sure, just be gentle..." He says quietly, looking back at Karasuma. Karasuma blushes, slowly pressing his tip against the octopus's entrance. Korosensei gritted his teeth at first, gasping as Karasuma suddenly slid in.
         "Ahh! K-Karasuma... P-perhaps I should've s-stretched myself out before taking your length-" He admits, embarrassed. Karasuma huffs.
          "You waited till now to tell me that?! Uhg... It doesn't matter... Just let me know if I hurt you okay?" He gently pushed all the way, earning a small moan from Korosensei.
"Nyu...~" Karasuma snickers.
"That's how you moan? Heheh... Cute.~" He rubs Korosensei's sides, slowly sliding in and out, making Korosensei shudder and push his butt out.
"Nyu...~~ Ahhh...~ Karasuma...~~" He smushed his face into the bed, clutching at the blankets. Karasuma moaned quietly, watching Korosensei touch himself as he thrusted into him.
"Mind giving me some of that a-AcTiOn!~" He moaned suddenly as the small tentacle inside him suddenly pressed against his prostate. He'd forgotten it was in there.
"Ahh...~ Alright hold still..." He started slowly picking up his pace, Korosensei pleasuring himself and Karasuma as he did this.
"Ah- Fuck Octopus...~ Rrr...~" He bit his lip, quickly starting to lose himself in the pleasure, quickly speeding up. Korosensei whimpered, but didn't complain, pumping the tentacle into Karasuma at the same pace.
"Ahhh!~ Are you liking this?~ Hmm?~" He squeezed Korosensei's ass firmly. The octopus moaned into the bed.
"Mmph!!~~~ Karasuma!~~" His words were muffled, but Karasuma knew he was enjoying it. He picked up his pace to full speed, slamming into Korosensei. The wet sounds of sex filled the bedroom.
"HNNG!!~ H-hold still!~~" Karasuma huffed, feeling his length twitch inside Korosensei. Korosensei's suddenly came onto the bed, moaning sharply.
"HNYAA!!!~~~~" Korosensei huffed, spamming for a moment. Karasuma looked disappointed, pulling out, his hadn't quite come yet.
"Y-you had to come early?" He asks. Korosensei sat up, grinning mischievously.
"Of course! If I hadn't, then I wouldn't get to tease you.~" He curls a tentacle around the base of Karasuma's length, which would prevent him from coming.
             "You can't be serious..." He says with a hint of dread as Korosensei leaned his head down to Karasuma's length.